Change of glutamic acid decarboxylase antibody and protein tyrosine phosphatase antibody in Chinese patients with acute-onset type 1 diabetes mellitus

Background Glutamic acid decarboxylase antibody （GADA） and protein tyrosine phosphatase antibody （IA-2A） are two major autoantibodies, which exert important roles in the process of type 1 diabetes mellitus （T1D）. Our study aimed to investigate the changes in positivity and titers of GADA and IA-2A during the course of Chinese acute-onset T1D patients and their relationships with clinical features.

Diagnostic role of antibodies to glutamic acid decarboxylase in latent autoimmune diabetes mellitus in adults

Objective To investigate the diagnostic role of antibodies to glutamic acid decarboxylase (GAD 65 Ab) in latent autoimmune diabetes of adults (LADA) and the frequency of GAD Ab in Chinese patients initially diagnosed as non insulin dependent diabetes mellitus (NIDDM) Methods Forty five control subjects and 195 consecutive inpatients initially classified as NIDDM with ≥35 years of age at onset and nonketotic history for >6 months after diagnosis, were recruited In vitro transcripted and translated recombinant human 35 S GAD 65 was used in radioligand assay of GAD Ab Results The overall prevalence of GAD 65 Ab was 14 8% (29/195) in NIDDM patients and 2 2% (1/45) in control subjects, respectively Of the 29 GAD 65 Ab positive patients, 17 (58 6%) were insulin deficient while 12 (41 4%) were non insulin deficient The prevalence of GAD 65 Ab in NIDDM group with age of <40 years at diabetes onset, ketotic history, body mass index (BMI) <21 kg/m 2, were significantly higher than that of corresponding control diabetic subgroups (2 5, 4 1 and 3 2 times, respectively) The sex, duration, symptoms of polyphagia, polydipsia, polyuria and weight loss at onset of the disease were not related to the prevalence of GAD 65 Ab positivity Conclusions In China, patients initially diagnosed as NIDDM may in many cases suffer from LADA Testing by GAD 65 Ab may be of assistance to identifying LADA at the earliest stage of disease

The role of anti-glutamic acid decarboxylase autoantibodies in mood disorders

Gamma-aminobutyric acid(GABA)possibly plays a causative role in mood disorders.This hypothesis originated with studies on the beneficial effect of valproate in mania and as a mood stabilizer.Since valproate is known for its action in increasing the level of GABA,it was indirectly suggested that decreasing levels of GABA were responsible for mood alterations.To identify factors causing the decreased levels of GABA,studies have concentrated on the activity of the enzyme L-glutamic acid decarboxylase(GAD),which catalyzes the transformation of glutamate to GABA,as a decreasing function of this enzyme induces lower levels of the neurotransmitter.Moreover,a very limited amount of research investigated the possible role of glutamic acid decarboxylase antibodies(GADA)in determining a decreased enzymatic function of GAD.If these findings are confirmed,it will be possible to improve diagnosis and treatment of mood disorders.In addition,if the presence of GADA is associated with a genetic trait,this would allow and facilitate early diagnoses.